This invention relates to a motor-operated pump of the in-tank type adapted to be sunk in a liquid fuel tank of a vehicle such as an automobile.
FIGS. 5 to 7 show a conventional motor-operated pump of the in-tank type as disclosed in Japanese Laid-Open (Kokai) Patent Application No. 272994/88. In these Figures, a motor 1 serving as a pump drive source comprises a rotor 2, a commutator 3 of the rotor 2, and brushes 4 held in contact with the commutator 3 so as to supply electric power to the rotor 2. There are further provided an impeller 6 connected to a shaft 5 of the rotor 2 and forming the pump, an intake port 7 of the pump, a motor casing 8, a bracket 9 of the motor 1, an outer cover 10, a discharge port 10a of the pump, a terminal 11 mounted on the cover 10 so as to be supplied with electric power from the outside, brush springs 12 for urging the brushes 4 against the commutator 3, noise prevention elements 13 for preventing electrical noise, and the like. Internal terminals 13a are engaged with the terminal 11 supplied with electric power from the outside. Relay terminals 13b serve as a holder for the brush spring 12, and also serve as a relay terminal connected to a lead wire 4a extending from the brush 4.
In this arrangement, when electric power is supplied to the terminal 11, the electric power is transferred to the rotor 2 via the noise prevention elements 13, the brushes 4 and the commutator 3 for driving the rotor 2. As a result, the impeller 6 connected to the rotor 2 is rotated, so that fuel is drawn through the intake port 7 and is fed to an engine (not shown) or the like via the discharge port 10a.
In the foregoing motor-operated pump of the in- tank type, as described above, the power supply portion inserted into the bracket 9 for supplying electric power to the motor 2 is composed of many parts including the noise prevention elements 13, the brushes 4, the brush springs 12, and the like. This raises problems, in that the construction is complicated, and that since the springs and other parts are mounted at the same time, the assembling operation is difficult.